ISSN:
1432-0819
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
Notes:
Abstract During the summer of 1982 a continuous uplift began at Phlegraean Fields, an active volcanic area in southern Italy (Fig. 1), that persisted up to September 1984. The uplift, which reached a maximum value of about 160 cm in the central part of the Phlegraean caldera, was characterized by variable velocity and occurred within an area that extended about 7 km outward from the town of Pozzuoli (Fig. 1); the surface deformation performs a bell-shape pattern. The uplift was accompanied by horizontal displacements and gravity changes that closely correlate with the described elevation changes. The horizontal displacements displayed an anomalous pattern within a narrow belt about 1 km from the center of the uplift and approximately coincident with the area of maximum seismic activity. The change in gravity is attributed primarily to a free-air effect to which a small Bouguer effect must be added. Several models have been invoked in order to explain the observed phenomenon. The one which gives the best fit to the observed data is an increasing pressure source of radial simmetry, at a constant depth of about 3 km beneath the town of Pozzuoli, and having a diameter of several hundred meters. Migration of magma at depth is believed to be responsible for the observed activity in the Phlegraean Fields caldera.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01961548
